Dispenser with Sealed Chamber, One-Way Valve and Needle Penetrable and Laser Resealable Stopper

ABSTRACT

A syringe is provided for the delivery of controlled, metered amounts of any of numerous different substances to humans or animals, such as medicaments, pharmaceuticals, cosmetics, and food products, or to deliver materials which may react upon exposure to air, such as glue. The syringes include a body and a plunger. Means are provided in the syringe body and the plunger to effect controlled movement of the plunger into the syringe to permit delivery of a pre-determined amount of the substance contained in the syringe. A one-way valve is provided at the dispensing tip of the syringe to hermetically seal the portion of the syringe containing the substance to be dispensed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of Ser. No. 11/195,520 filedon Aug. 1, 2005, entitled “Dispenser with Sealed Chamber, One-Way Valveand Needle Penetrable and Laser Resealable Stopper,” now U.S. Pat. No.7,290,573, which in turn claims priority to U.S. patent application Ser.No. 10/272,577 filed on Oct. 16, 2002 entitled “Dispenser with SealedChamber and One-Way Valve for Providing Metered Amounts of Substances”,which in turn claims priority to U.S. Provisional Patent ApplicationSer. No. 60/329,779, filed Oct. 16, 2001, entitled “Syringe ForProviding Metered Amounts Of Substances”, and is related to U.S.Provisional Patent Application Ser. No. 60/403,484 filed on Aug. 13,2002, entitled “Dispensing With Sealed Chamber And One-Way Valve ForProviding Material Amounts of Substances,” and U.S. Provisional PatentApplication Ser. No. 60/403,396, filed Aug. 13, 2002, entitled“Container For Storing And Dispensing Sterile Substances And Method OfMaking And Filling Same”, each of which is hereby expressly incorporatedby reference as part of the present disclosure.

FIELD OF THE INVENTION

The present invention relates to syringes and like dispensers fordelivering any of numerous different substances to humans or animals,such as medicaments, pharmaceuticals, cosmetics, and food products, orto deliver materials which react upon exposure to air, such as glues.The dispensers of the present invention include fusible or otherstoppers connected to, or otherwise forming the plungers, forhermetically sealing the interfaces between the plungers and theinteriors of the dispensers, and thereby preventing ingress of air orcontaminants through the plungers. The dispensers of the presentinvention also may include a one-way valve forming a dispensing tip, forhermetically sealing the dispensing tip and likewise preventing ingressof air or contaminants through the dispensing tip and into themedicaments or other substances contained within the dispensers. Bypreventing the ingress of air or contaminants to the substancescontained within the dispenser, the use of preservatives in thesubstances may be reduced or eliminated.

BACKGROUND OF THE INVENTION

Delivery of controlled doses of medicaments is desirable to avoidovermedication. Overmedication can especially occur when the medicamentis in the form of a creme or liquid. For example, while it is highlydesirable to carefully control the dosage of medicaments given toinfants or children, it can be difficult to measure the proper doseusing traditional measuring devices such as measuring cups. When themedicament is in the form of a creme or ointment, such as for examplecremes applied to the face to control skin acne, the medicaments areoften stored in tubes or other containers that do not provide deliveryof precise doses of the medicament. Application of excess amounts of thecreme can result in skin irritation and drying. Also, application ofcremes using fingers can result in contamination of the medicament.

For some medicaments, such as for example the antiseptic Betadyne™,delivery of a controlled dose in a precise location on the skin isdesirable to avoid excessive staining of skin or clothing. For certainvaccines, such as the vaccine for gastroenteritis, a hermetically sealeddispenser that can deliver multiple precise doses of the vaccine canreduce waste of both the vaccine and dispensers.

Several devices have been described previously which permit controlleddoses of medicaments to be delivered. These devices can be complicatedto manufacture, assemble and fill with the medicament. As a result,these devices can be expensive to manufacture and may not be useful forover the counter (“OTC”) medicaments. Another disadvantage of suchdevices is that air can enter the device during storage or as themedicament is delivered. Air entering the device during storage ordelivery of the medicament can cause degradation of the medicament,reducing the efficacy of the medicament or causing spoilage which mayrequire that the medicament be discarded.

For some medicaments, preservatives are added to prevent degradation orspoilage of the medicament before use due to ingress of air or othercontaminants. The preservatives can react with the medicament, however,reducing its efficacy. Also, some users can have undesirable adversereactions to the preservatives in the medicaments.

One-way spray tips for dispensing medicaments in aerosol form or fordelivery to the eye have been described in U.S. Pat. No. 5,320,845 toDr. Daniel Py issued on Jun. 14, 1994, U.S. Pat. No. 5,613,957 to Dr.Daniel Py issued on Mar. 25, 1997, U.S. Pat. No. 5,746,728 to Dr. DanielPy issued on May 5, 1998, U.S. Pat. No. 5,855,322 to Dr. Daniel Pyissued on Jan. 5, 1999 and U.S. Pat. No. 6,053,433 to Dr. Daniel Pyissued on Apr. 25, 2000, each of which is hereby incorporated byreference as part of the present disclosure.

Cosmetics, such as cremes or liquid make-ups, can also degrade or spoilwith exposure to air. Accordingly, it would be desirable to provide adispenser that could prevent the ingress of air or other contaminantsinto the medicament, cosmetic or other substance contained within thedispenser, as well as provide improved control of the amount of thesubstance dispensed therefrom. It also would be desirable to provide ahermetically sealed dispenser that could be used to deliver controlledamounts of other air-sensitive substances, such as for example glues,while preserving unused portions of the substance for later use.

Accordingly, it is an object of the present invention to overcome one ormore of the drawbacks and/or disadvantages of the prior art.

SUMMARY OF THE INVENTION

The present is directed to a dispenser adapted to be filled with asubstance by an apparatus including a needle for piercing the dispenserand introducing the substance through the needle and into the dispenser,and an energy source, such as a laser, for thermally resealing anaperture in the dispenser after withdrawal of the needle therefrom. Thedispenser comprises a body defining a chamber for receiving thesubstance and a one-way valve mounted on the body. The one-way valveincludes an axially-elongated valve seat, and an axially-elongatedflexible valve member secured to the valve seat and defining anormally-closed valve opening at the interface of the valve member andvalve seat that is connectable in fluid communication with the chamber.A piston or plunger is mounted within the body and movable axiallytherethrough for varying the volume of the chamber upon dispensingsubstance from the chamber through the one-way valve. A resealablestopper is in fluid communication with the chamber and is penetrable bythe needle for introducing the substance through the stopper and intothe chamber. The resealable stopper includes a penetrable region that isfusible in response to the application of thermal energy from the energysource thereto hermetically seal an aperture in the penetrable regionafter removing the needle therefrom.

In one embodiment of the present invention, the heat-resealable orfusible stopper is included at the base of the plunger. In one suchembodiment, the fusible stopper includes a vulcanized rubber base and aninsert made of a heat-sealable material. In another such embodiment, thestopper is made of blend of polymeric materials that may be heatresealed by the application of laser energy or like radiation thereto.The chamber for storage of the substance is filled by inserting a needlethrough the fusible stopper and in fluid communication with the chamber.In one such embodiment, as the storage chamber is filled, the air in thestorage chamber is allowed to escape past a flexible flap on the outerperiphery of the fusible stopper or through an aperture formed withinthe needle (e.g., a double lumen needle) or between the needle andstopper. After the storage chamber is filled, the heat sealable materialof the stopper is heated to fuse the hole created by the needle, and theflexible flap on the outer periphery of the fusible stopper returns toits normal position to hermetically seal the storage chamber.

In accordance with one embodiment of the present invention, the energysource is a laser that transmits laser radiation at a predeterminedwavelength and power. The penetrable region of the resealable stopper isheat resealable to hermetically seal the needle aperture by applyinglaser radiation from the laser at the predetermined wavelength and powerthereto. The stopper comprises a thermoplastic body defining (i) apredetermined wall thickness in an axial direction thereof, (ii) apredetermined color and opacity that substantially absorbs laserradiation at the predetermined wavelength and substantially prevents thepassage of radiation through the predetermined wall thickness thereof,and (iii) a predetermined color and opacity that causes the laserradiation at the predetermined wavelength and power to hermetically seala needle aperture formed in the needle penetration region thereof in apredetermined time period of less than approximately 2 seconds andsubstantially without burning the needle penetration region. In one suchembodiment, the predetermined wavelength of the laser is about 980 nm,the predetermined power of the laser is within the range of about 8 to10 Watts, the predetermined color of the resealable stopper is gray, andthe predetermined opacity of the resealable stopper is defined by a darkgray colorant additive within the range of about 0.3% to about 0.6% byweight

Another embodiment of the present invention includes means forpreventing residual seepage of substance through the one-way valve. In acurrently preferred embodiment, the body defines a plurality of firstthreads and the plunger defines a plurality of second threads engageablewith the first threads for moving at least one of the plunger and bodyrelative to the other. In this embodiment, the means for preventingresidual seepage is defined by an axial spacing formed between first andsecond threads. The axial spacing is sufficient to allow at least one ofthe plunger and body to move axially relative to the other afterdispensing a metered amount of substance through the one-way valve to,in turn, reduce and/or eliminate any pressure differential between thechamber containing the substance and the exterior of the dispenser.

One advantage of the currently preferred embodiments of the presentinvention is that the dispensers are capable of delivering controlleddoses of any of numerous different substances, such as pharmaceutical,vaccine, drug or other medicinal preparations or formulations, cosmeticproducts, food products, and industrial or other household products,such as glues. The currently preferred embodiments of the presentinvention are relatively inexpensive to manufacture; thereby allowingthe dispensers to be used with a wide variety of substances, includingliquids, cremes, ointments, pasty products and other fluids andsubstances.

Another advantage of the present invention is that the one-way valve atthe dispensing tip of the dispenser hermetically seals the tip andprevents the ingress of air or other contaminants into the substancecontained in the dispenser, thereby allowing the substance to be storedwithout preservatives and further allowing multiple doses of suchnon-preserved substances to be contained in the dispenser.

Other advantages of the syringes and other dispensers of the presentinvention will become more readily apparent in view of the followingdetailed description of currently preferred embodiments of the presentinvention, claims and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those having ordinary skill in the art to which the subjectinvention appertains will more readily understand the subject invention,reference may be had to the drawings, wherein:

FIG. 1 a is a frontal perspective view of a syringe-type dispenserembodying the present invention and showing the plunger partiallyinserted in the syringe body.

FIG. 1 b is a rear perspective view of the syringe of FIG. 1 a showingthe plunger partially inserted in the syringe body.

FIG. 2 is a frontal perspective view of the body of the syringe of FIG.1 a.

FIG. 3 is a rear perspective view of the body of the syringe of FIG. 1 ashowing the helical steps formed on the inner surface of the upperportion of the body.

FIG. 4 is a cross-sectional view of a first half of the body takenthrough section A-A of FIG. 2 and showing the inner walls of the body.

FIG. 5 is a cross-sectional view of a second half of the body takenthrough section A-A of FIG. 2 and showing the inner walls of the body.

FIG. 6 a is a frontal perspective view of the plunger of the syringe ofFIG. 1 a.

FIG. 6 b is a rear perspective view of the plunger of the syringe ofFIG. 1 a.

FIGS. 7 a-7 c are somewhat schematic, partial cross-sectional views ofthe syringe of FIG. 1 a showing the means for controlling the travel ofthe plunger within the body, and illustrating the progressive movementof the plunger within the body.

FIG. 8 is a partial, cross-sectional view of the syringe of FIG. 1 aincluding a fusible stopper at the base of the plunger inside thestorage chamber of the body.

FIG. 9 is a partial, cross-sectional view of the fusible stopper of thesyringe shown in FIG. 8.

FIG. 10 is a cross-sectional view of the fusible stopper and body ofFIG. 9.

FIG. 11 is a perspective view of a second embodiment of a syringe-typedispenser of the present invention illustrating the body includingpartially threaded portions and a plunger with a threaded upper guideportion for controlling travel of the plunger.

FIG. 12 is a partially broken away, perspective view of the syringe ofFIG. 11.

FIGS. 13 and 14 are cross-sectional views of the syringe of FIG. 11.

FIG. 15 is a cross-sectional view of the body and the upper guideportion of the plunger of FIG. 11.

FIG. 16 is a side elevational view of the plunger of the syringe of FIG.11.

FIG. 17 is a partially enlarged elevational view of FIG. 16 showing aportion of the threads on the upper guide portion of the plunger.

FIG. 18 is a partially broken away, perspective view of a thirdembodiment of a syringe-type dispenser of the present invention havingan elastomeric outer cover.

FIG. 19 is a perspective view of the syringe of FIG. 18, with a portionpartially broken away to show the elastomeric outer cover, threadedelements and upper guide portion of the plunger.

FIG. 20 is a partial cross-sectional view of the body and upper guideportion of the syringe of FIG. 18.

FIG. 21 is a partial, perspective view of the body of FIG. 18 with aportion broken away to show the threaded elements in the upper portionof the body.

FIG. 22 is a cross-sectional view of another embodiment of asyringe-type dispenser including means for preventing residual seepageof the hermetically sealed substance through the dispensing tip andshowing the plunger in the fully-extended position.

FIG. 23 is a cross-sectional view of the syringe-type dispenser of FIG.22 showing the plunger in the retracted position.

FIG. 24 is a partial, perspective view of the body of FIGS. 22 and 23showing the discrete, axially-extending thread segments formed on theinner wall of the body.

FIGS. 25 through 27 are somewhat schematic, cross-sectional views of thesyringe-type dispenser of FIGS. 22 and 23 showing the progression ofrotatable movement of the threaded plunger within the threaded bodythrough ¼ turn.

FIG. 28 is a partial, somewhat schematic view of the syringe bodythreads and plunger threads, and illustrating the axial play of theplunger when located in the rest position in order to prevent residualseepage of the sealed substance through the dispensing tip.

FIG. 29 is a partial, perspective view of the plunger of FIGS. 22 and23, with parts removed for clarity, and illustrating the differentthread segments of the plunger.

FIG. 30 is a cross-sectional view of the plunger of FIG. 29 furtherillustrating the different thread segments of the plunger.

FIG. 31 is a cross-sectional view of another embodiment of asyringe-type dispenser including a concealed plunger and a drivemechanism for rotatably moving the plunger through the syringe body, andillustrating the plunger in the fully-extended position.

FIG. 32 is a cross-sectional view of the syringe-type dispenser of FIG.31 illustrating the plunger in a retracted position.

FIG. 33 is a cross-sectional view of another embodiment of asyringe-type dispenser including a concealed plunger and a drivemechanism for rotatably moving the plunger through the syringe body, andillustrating the plunger in a retracted position.

FIG. 34 is a cross-sectional view of the syringe-type dispenser of FIG.33 illustrating the plunger in an extended position.

FIG. 35 is a partial, cross-sectional view of another embodiment of asyringe-type dispenser of the present invention including a dispensingtip shaped to conformably contact a user's lips or other surface contourfor cosmetic applications.

FIG. 36 is a side elevational view of the syringe-type dispenser of FIG.35.

FIG. 37 is a partial, cross-sectional view of another embodiment of asyringe-type dispenser of the present invention including anotheruniquely-shaped dispensing tip for cosmetic applications.

FIG. 38 is a perspective view of another syringe-type dispenserincluding a concealed plunger and a drive mechanism for rotatably movingthe plunger in a step-wise manner through the syringe body.

FIG. 39 is a perspective, exploded view of the syringe-type dispenser ofFIG. 38.

FIG. 40 is another perspective, exploded view of the syringe-typedispenser of FIG. 38.

FIG. 41 is a partial cross sectional view of the fusible stopper of thesyringe shown in FIG. 8, and an energy source for sealing a resealablemember.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to improved syringes and other dispensersfor delivery of substances, such as vaccines, medicaments and otherpharmaceutical preparations, cosmetics, food products, glues, or anyother substance that can spoil, degrade or react with air. As shown inFIGS. 1 a and 1 b, the improved syringe-type dispensers include a body12 and a plunger 14. Means are provided for controlling the travel ofthe plunger 14 in the syringe body 12 which results in delivery of aprecise amount of the substance from the syringe. As shown in FIG. 8, aheat-resealable or other type of stopper is provided at the tip of theplunger to hermetically seal the lower or storage chamber of the syringeand prevent ingress of air or contaminants into the substance in thesyringe. In addition, as shown in FIG. 1, the tip of the syringe 16 usedfor delivery of the substance preferably includes a one-way valve toprevent exposure of the substance to air or other contaminants thatotherwise might enter through the tip of the syringe. The preferredembodiments disclosed herein are to be considered exemplary of theprinciples of the present invention and are not intended to limit theinvention to the embodiments described. Various modifications will beapparent to those skilled in the art based on the teachings hereinwithout departing from the spirit or scope of the invention disclosedherein.

As used herein, the term “syringe” or “syringe-type dispenser” means adevice having a plunger or like element movable through a chambercontaining a substance, such as a liquid, creme, ointment or fluid, inorder to inject or deliver the substance into a body, onto the skin, oronto the surface of an object. In addition, the term “plunger” is usedherein to mean a device used to exert pressure on the substancecontained in the chamber in order to dispense the substance from thedevice.

Syringe-Type Dispenser with Cam-Like Members for Stepwise Movement

In FIGS. 1 a-7 c, a first embodiment of a syringe-type dispenser of thepresent invention is indicated generally by the reference number 10. Asshown in FIGS. 1 a and 1 b, the syringe includes a body 12, a plunger 14which fits within the syringe body, and a dispensing tip 16 with aone-way valve 54. The body 12 and plunger 14 are preferably made of amoldable plastic, although the invention is not limited in this regardand any appropriate material that is currently or later becomes known toone skilled in the art may be used.

Referring to FIG. 2, the body 12 of the syringe 10 is generallycylindrical. In the embodiment of the invention illustrated in FIG. 2,the syringe body has an upper portion 18 and a lower portion 20, whereinthe upper portion has a larger diameter than the lower portion. Theupper portion 18 is connected to the lower portion 20 by a taperedportion 22. The invention is not limited in this regard, however, andthe upper portion and the lower portion may be any desired dimension orshape. Where the diameters of the upper portion and the lower portionare the same, the tapered portion may be eliminated.

At the outer end of the upper portion 18 opposite the tapered portion22, means may be provided for gripping the syringe during use. In theembodiment of the invention illustrated in FIG. 2, two opposing flatmembers 24 protrude perpendicularly from the top of the upper portion ofthe syringe for gripping the syringe during use. The flat members 24 arepreferably approximately triangular in shape, although any desired sizeor shape may be used.

As shown in FIGS. 3-5, the inner walls of the upper portion 18 and thelower portion 20 define cylindrical cavities. The inner wall of theupper portion 18 of the syringe body includes a plurality of steps 34defining an approximately helical path. As shown in FIGS. 4 and 5, whichshow opposing halves of the inside of the body of the syringe throughsection A-A of FIG. 2, the inner wall of the upper portion 18 of thesyringe body 12 defines two helical sets of steps 34 formed on oppositesides of the inner wall 36 of the upper portion 18 of the syringe bodyrelative to each other. Each set of steps 34 define an approximatelyhelical path. As shown in FIG. 4, one set of steps 34 is oriented toallow travel along the steps in the direction from the top of the upperportion 18 toward the tapered portion 22 of the syringe body. As shownin FIG. 5, the second set of steps 34 is oriented in the oppositedirection relative to the other set of steps to prevent rearwardmovement of the plunger 14, as described further below.

As shown in FIGS. 7 a-7 c, the inner wall 38 of the lower portion 20 ofthe syringe body 12 defines a smooth cylindrical cavity and has anapproximately constant inner diameter over the axial length of the lowerportion 20. The lower portion 20 of the syringe defines a storagechamber for storing the substance to be dispensed, and is dimensioned tofrictionally engage the base of the plunger, as described further below.The inner diameter of the lower portion 20 is preferably constant toensure that a specific quantity of the medicament or other substancecontained therein is dispensed from the syringe for a pre-determineddistance of travel by the plunger 14.

At the end of the lower portion of the syringe body, a dispensing tipindicated generally by the reference number 16 is provided to allow themedicament to flow from the syringe as the plunger is inserted into thelower portion. As shown in FIG. 2, in one embodiment of the presentinvention, the dispensing tip 16 includes a flange 28 that defines anannular U-shaped channel 30. The dispensing tip defines a valve seat inthe form of an elongated center shaft or post 32. A plurality ofopenings (not shown) are provided around the base of the center shaft32. Each of the plurality of openings communicates with the chamber inthe lower portion 20 of the syringe to provide a path to dispense thesubstance contained in the syringe. A one-way valve 54, such as theone-way valve described below, is included at the dispensing tip toallow controlled delivery of the substance and to hermetically seal thedispensing tip and thereby prevent exposure of the substance in thesyringe to air or contaminants. In an alternative embodiment, the centershaft 32 may be provided with a central cylindrical channel thatcommunicates with the chamber in the lower portion of the syringe toprovide a path for dispensing the substance contained in the syringe. Inother embodiments, other dispensing tip mechanisms that are currently orlater become known to those skilled in the art can be fixedly attachedto the syringe body. For example, the conventional connection devicemarketed under the trade name LUER-LOK can be used at the dispensing tipof the syringe to allow attachment of disposable needles. Other needleconnection means, such as threaded fittings, elastomeric plugs, orfitted end caps equally may be used to attach a needle to the end of thesyringe. The lower end of the syringe body may be shaped or threaded asrequired to accommodate the selected needle connection means. A cap orother means (not shown) to hermetically seal the dispensing end of thesyringe may be used until the needle is connected to the syringe todispense the medicament or other substance therein.

Referring now to FIGS. 6 a and 6 b, the plunger 14 comprises a base ortip 40, a lower drive portion 42, and an upper guide portion 44. Thefront surface 46 of the tip 40 contacts the substance in the storagechamber in the lower portion 20 of the syringe during use. The tip 40 isshaped and dimensioned to fit frictionally into the chamber in the lowerportion 20 of the syringe body such that the substance does not escapebetween the base and the inner surface of the lower portion 20 of thesyringe as the tip 40 is inserted into the lower portion 20. The tip 40is preferably made from a material that will not react with thesubstance in the syringe, such as any of numerous different moldable,resilient plastics that are currently or later become known forperforming the function of the plunger tip described herein. Inaddition, the plunger tip 40 is preferably made of a resilient materialthat will hermetically seal the substance within the chamber formed bythe body of the syringe, such as the heat resealable stopper describedfurther below, or any of numerous other plunger tip materials that arecurrently or later become known for performing the function of theplunger tip as described herein.

The drive portion 42 of the plunger 14 is shaped and dimensioned to fitslidingly within the lower portion 20 of the syringe body. The outsidediameter of the drive portion 42 is preferably at least slightly lessthan the inside diameter of the lower portion 20 of the syringe body toreduce the frictional force generated by movement of the plunger withinthe syringe body. The lower drive portion 42 should be sufficiently longto be fully inserted into the chamber in the lower portion 20 of thesyringe body.

The upper guide portion 44 of the plunger 14 defines twodiametrically-opposed, cam-like members 48 that extend perpendicularlyfrom the outside surface of the upper guide portion of the plunger. Thecam-like members 48 cooperate with the steps 34 formed on the inner wall36 of the upper portion 18 of the syringe body to provide means forcontrolling the travel of the plunger into the syringe in a stepwisemanner. As shown in FIG. 7 a, the cam-like members 48 are preferablylocated on the upper guide portion 44 such that the base 40 of theplunger is in contact with the medicament or other substance containedin the cavity in the lower portion 20 of the syringe body when thecam-like members 48 engage the steps 34 formed on the inner wall of theupper portion 18 of the syringe body 12. As shown in FIGS. 6 a and 7 a,the outside surface of the upper guide portion 44 of the plunger 14preferably includes a plurality of vanes 50 or other support means toprovide additional rigidity and/or strength to the plunger during use.The upper guide portion 44 should be sized and dimensioned to fitslidingly within the upper portion 18 of the syringe body. A knob orother griping portion 52 is formed at the upper end of the plunger 14 toprovide means for the user to grip the plunger during use.

The syringe 10 preferably includes a one-way valve mechanism at thedispensing tip of the syringe to prevent air or other contaminants fromentering the substance contained in the syringe through the dispensingend. Referring to FIGS. 1 a, 2 and 7 a, the one-way valve is formed byfixing a flexible cover 54 on the dispensing tip 16 of the syringe body.The flexible cover 54 is preferably made of an elastomeric material. Theinterior surface of the flexible cover 54 is shaped to fit over theflange 28 on the dispensing tip 16 and to fit integrally within theannular U-channel 30 which extends around the dispensing tip. Theflexible cover 54 forms an interference fit with the center shaft orvalve seat 32 on the dispensing tip. The flexible cover 54 extends fromthe outer surface of the lower portion 20 of the syringe body 12 toapproximately the end of the center shaft 32 of the dispensing tip 16.

At the base of the center shaft, and as shown typically in FIGS. 7 a-7c, a plurality of cylindrical openings 56 extend through the dispensingtip. The cylindrical openings 56 communicate with the storage cavity inthe lower portion 20 of the syringe and provide a path through which themedicament or other substance in the cavity in the lower portion 20flows as the plunger 14 is advanced into the lower portion 20 of thesyringe. The interference fit between the flexible cover 54 and thecenter shaft 32 forms a normally-closed valve to hermetically seal thecylindrical openings 56 until a dose of the substance contained in thesyringe is delivered. As shown, the portion of the flexible cover 54that interfaces with the valve seat 32 is preferably tapered such thatthe thickness is greater near the base of the valve seat and graduallyreduces to a lesser thickness near the end of the valve seat tofacilitate opening of the valve and the flow of substance therethrough.In addition, the axial length of each of the valve seat 32, valve cover54 and annular valve opening formed therebetween is sufficiently long toalways maintain an annular segment of the valve cover in contact withthe valve seat when dispensing substance through valve opening. As canbe seen, the valve cover 54 defines an aperture therethrough, the valveseat 32 is received within the aperture to form the normally-closedannular valve opening at the interface between the valve seat and valvecover, and the diameter (or width) of the valve seat is greater than thediameter (or width) of the aperture in the cover to thereby form aninterference fit and normally-closed valve opening therebetween.Preferably, the degree of interference between the valve cover apertureand valve seat decreases in the axial direction of the valve seat fromthe interior toward the exterior of the dispenser to facilitate the flowof substance therethrough.

As may be recognized by those of ordinary skill in the pertinent artbased on the teachings herein, the one-way valve of the dispensers maytake any of numerous different configurations that are currently orlater become known for performing the function of the valve describedherein, including any of the one-way valve configurations disclosed inthe above-mentioned co-pending patent application Ser. No. 60/403,484.

Referring again to FIGS. 7 a, 7 b and 7 c, to dispense the substancecontained in the syringe, the plunger 14 is rotated and depressed untilthe cam-like members 48 on the upper guide portion each travel down onestep 34 along the inner wall of the upper portion of the syringe. Asshown in FIG. 7 b, as the plunger assembly is rotated, the base 40 ofthe plunger travels into the lower chamber 20 of the syringe. The base40 exerts pressure on the substance in the lower chamber of the syringe,which causes the substance to flow into the cylindrical openings 56 atthe base of the center shaft 32 in the dispensing tip of the syringe.The pressurized substance, in turn, exerts force on the interior surfaceof the flexible valve cover 54, causing the flexible cover 54 to bemoved away from the center shaft 32, thereby allowing the substance toflow between the interior surface of the flexible cover 54 and thecenter shaft 32. When the plunger has advanced a pre-determined distanceto deliver the desired quantity of the substance contained in thesyringe, the force exerted on the substance is released and the flexiblecover returns to its normally closed position with the center shaft 32interfacing the interior surface of the flexible cover 54 to form ahermetic seal. As shown in FIG. 7 c, the plunger 14 can be inserted intothe syringe in a step-wise manner until the tip 40 of the plunger hastraveled completely through the chamber in the lower portion 20 of thesyringe and thereby dispensed all of the contained substance therefrom.

The cam-like members 48 cooperate with the steps 34 on the inner surfaceof the upper portion 18 of the syringe to limit the travel of theplunger. The distance that the base of the plunger travels is therebyprecisely controlled, and a precise volume of the medicament or othersubstance contained in the syringe can be delivered. The volume ofmedicament delivered is a function of the height of the step and theinside diameter of the lower chamber 20. By setting these twoparameters, the volume of substance delivered as a result of travel bythe plunger along a single step is precisely controlled and is equal tothe cross-sectional area of the inside of the lower chamber of thesyringe multiplied by the linear distance traveled by the plunger. Forexample, if the inside diameter of the lower chamber of the syringe is 6mm, and it is desired to have movement of the plunger by one step resultin delivery of 100 microliters of the substance contained in thesyringe, then the step height would be set at approximately 3.54 mm.Where the substance contained in the lower chamber includes an activeingredient and a carrier, the dose of active ingredient delivered mayalso be a function of the concentration of active ingredient in thecarrier. Delivery of a higher dose can be achieved by instructing theuser to move the plunger by the number of steps required to deliver thedesired amount of the substance. In the example provided above, movementby two steps would result in delivery of 200 microliters, etc.

Stopper to Hermetically Seal Lower Chamber of Syringe-Type Dispenser

In FIGS. 8-10, another syringe-type dispenser embodying the presentinvention is indicated generally by the reference numeral 110. Many ofthe components of the syringe 110 are the same as those in the syringe10 described above with reference to FIGS. 1 a-7 c, and therefore likereference numerals preceded by the numeral “1”, are used to indicatelike elements. The primary difference of the syringe 110 in comparisonto the syringe 10 is that the syringe 110 includes a fusible stopper 160at the base of the plunger 114 to hermetically seal the cavity in thelower portion 120 of the syringe 110 and thereby prevent ingress of airor contaminants into the medicament or other substance contained in thesyringe.

As shown in FIGS. 8 and 9, the fusible stopper 160 is formed at the endof the plunger 114 and includes a resilient base 162 made of vulcanizedrubber or other material which is known to those of ordinary skill inthe pertinent art, and acceptable for use in the manufacture of stoppersplaced in contact with or otherwise exposed to the substance to becontained within the syringe. The lower portion 164 of the base 162 ofthe fusible stopper 160 defines a peripheral sealing surface 166 that isshaped and dimensioned to slidably and frictionally engage the innerwall of the lower portion 120 of the syringe body 112. The base 162 ofthe fusible stopper further defines a peripheral wall 168 extending fromthe lower portion 164 of the base 162. The peripheral wall 168 definesan outer diameter slightly less than that of the sealing surface 166 andthe inner diameter of the syringe body 112 to reduce the frictionbetween the fusible stopper and the body of the syringe upon movement ofthe plunger therein.

At the upper end of the peripheral wall 168, an annular raised portionor protuberance 170 dimensioned to be frictionally received within thelower portion 120 of the syringe body 112 further seals the plungerassembly 114 and prevents air from contacting the medicament or othersubstance contained in the syringe. At the top of the peripheral wall168, a wedge-shaped flexible annular flap 172 is present, which isshaped and dimensioned to be flexible and to contact the inside of thesyringe body 112 to form the annular one-way valve. The tip 174 of theflexible flap 172 makes contact with the inside of the syringe body 112when the plunger is in its fully-retracted position. As shown in FIG. 9,in the illustrated embodiment of the invention, the inside diameter ofthe syringe body 112 in the area of the flexible flap 172 may beslightly larger than the inside diameter of the syringe at the base 164of the fusible stopper 160 when the plunger is in the illustratedretracted position. As the plunger is advanced into the syringe body112, the inside diameter of the body of the syringe body 112 decreasesslightly, causing the flexible flap 172 to make increased contact withthe syringe body, thereby sealing the lower portion of the syringe fromingress of air.

As shown in FIGS. 9 and 10, the inner wall of the lower portion 120 ofthe syringe body 112 is provided with a plurality of axially-elongatedgrooves 176 angularly spaced relative to each other about the axis ofthe syringe. The grooves 176 are formed in the inner wall of the lowerportion 120 and extend in an axial direction from below the base 162 ofthe fusible stopper 160 when in the fully-retracted position andupwardly beyond the annular protuberance 170. As described below, thegrooves 176 allow air contained in the syringe to escape as the syringeis filled with a medicament or other substance.

A rescalable member 178 is contained within the upper recess 179 of thebase 160 defined by the peripheral wall 168. The resealable member 178is received within the upper recess 179 formed in the peripheral wall168 of the base 160, and is secured in place by the end of the driveportion 142 of the plunger. The interior surface of the peripheral wall168 of the fusible stopper is shaped with an annular groove 180. Anannular flange 181 is formed at the end of the drive portion 142 of theplunger 114 and is dimensioned and shaped complementary to the annulargroove 180 on the interior surface of the peripheral wall 168.Accordingly, the annular flange 181 is pressed, snapped or otherwisereceived within the annular groove 180 to fixedly secure the fusiblestopper 160 to the drive portion 142. A second annular flange 182 isaxially spaced relative to the first annular flange 181 to capture andretain the base 162 and the resealable stopper 160 on the drive portion142. In the embodiment of the invention shown in FIGS. 8 and 9, thedrive portion 142 is in the form of a hollow tube to allow insertion ofa filling needle to fill the chamber 120, and allow resealing of theneedle hole after filling, as described in commonly assigned U.S. patentapplication Ser. No. 09/781,846, filed Feb. 12, 2001, entitled“Medicament Vial Having A Heat-Sealable Cap, And Apparatus And MethodFor Filling The Vial”, which is hereby expressly incorporated byreference as part of the present disclosure.

The resealable member 178 is preferably made of a resilient polymericmaterial, such as a blend of the polymeric material sold by Shell OilCo. under the registered trademark KRATON® and a low-densitypolyethylene, such as the polyethylene sold by Dow Chemical Co. underthe trademarks ENGAGE™ or EXACT™. However, any other appropriatematerial known to one skilled in the art may be used. An importantfeature of the resealable member 178 is that it be resealable to form agas tight seal after inserting a needle or like injection member throughthe resealable member. Preferably, the resealable member 178 can besealed by heating the area punctured by the needle in a manner known tothose skilled in the pertinent art, such as, for example, the methoddescribed in the above-mentioned co-pending patent application.

To fill the lower portion 120 of the syringe with the desired substance,a hypodermic needle, a double lumen needle, or other type of injectionmember is inserted through the resealable member 178 and the resilientbase 162 of the fusible stopper 160 in order to dispense the desiredsubstance into the lower portion 120 of the syringe. As the medicamentis injected into the lower portion of the syringe, the air within thelower portion is displaced by the substance and forced out. The airescapes through the plurality of grooves 176 formed in the inner wall ofthe syringe body 112. At the top of the peripheral wall 168, the forceof the escaping air causes the flexible flap 172 of the one-way valve tomove away from the inner wall of the syringe body, allowing the air topass out of the syringe body. When the syringe has been filled withmedicament or other substance, the flexible flap 172 returns to itsnormal position in contact with the syringe body 112, thereby forming ahermetic seal to prevent air from entering the syringe and contactingthe medicament or other substance therein. As the plunger is insertedinto the lower portion 120 of the syringe, the grooves 140 terminate,and the lower portion is further sealed by the peripheral sealingsurface 166 and the annular protuberance 170 on the resealable stopper160.

After the syringe 110 is filled with the medicament or other substance,the resealable member 178 is heated to fuse the hole formed by theneedle or other filling member. In a currently preferred embodiment ofthe present invention, a laser 191 (shown for example in FIG. 41) orother radiation source is used to sterilize the surface of theresealable member prior to filling, and to seal the hole remaining afterfilling. Preferably, the syringe is filled in a sterile filling machine,and in accordance with the method disclosed in the co-pending patentapplication incorporated by reference above. The laser allows sufficientenergy 193 to be directed to the resealable member in the fusiblestopper while avoiding heating of the medicament or other substance inthe syringe. Other methods of heating the resealable member that arecurrently or later become known to those skilled in the art may be useddepending on the heat sensitivity of the substance contained in thesyringe and/or other factors. Because the syringe is hermetically sealedafter it is filled with medicament or other substance, the syringe maybe stored for extended periods of time without spoilage due to ingressof air and without the addition of preservatives to prevent suchspoilage.

In certain embodiments of the present invention, at least a portion ofthe resealable stopper is formed of a thermoplastic material defining aneedle penetration region that is pierceable with a needle to form aneedle aperture therethrough, and is heat resealable to hermeticallyseal the needle aperture by applying laser radiation at a predeterminedwavelength and power thereto. In an alternative embodiment of thepresent invention, the entire body of the stopper is formed of thethermoplastic material. In another embodiment of the invention asdescribed above, an overlying portion of the stopper if formed of thefusible thermoplastic material, and an underlying portion of the stopperis formed of an infusible material, such as vulcanized rubber.Preferably, each thermoplastic portion or body defines (i) apredetermined wall thickness in an axial direction thereof, (ii) apredetermined color and opacity that substantially absorbs the laserradiation at the predetermined wavelength and substantially prevents thepassage of the radiation through the predetermined wall thicknessthereof, and (iii) a predetermined color and opacity that causes thelaser radiation at the predetermined wavelength and power tohermetically seal the needle aperture formed in the needle penetrationregion thereof in a predetermined time period and substantially withoutburning the needle penetration region (i.e., without creating anirreversible change in molecular structure or chemical properties of thematerial). In one embodiment, the predetermined time period isapproximately 2 seconds, is preferably less than or equal to about 1.5seconds, and most preferably is less than or equal to about 1 second.Also in this embodiment, the predetermined wavelength of the laserradiation is about 980 nm, and the predetermined power of each laser ispreferably less than about 30 Watts, and most preferably less than orequal to about 10 Watts, or within the range of about 8 to about 10Watts. Also in this embodiment, the predetermined color of the materialis gray, and the predetermined opacity is defined by a dark graycolorant added to the stopper material in an amount within the range ofabout 0.3% to about 0.6% by weight.

In addition, the thermoplastic material may be a blend of a firstmaterial that is preferably a styrene block copolymer, such as thematerials sold under either the trademarks KRATON or DYNAFLEX, and asecond material that is preferably an olefin, such as the materials soldunder either the trademarks ENGAGE or EXACT. In one embodiment of thepresent invention, the first and second materials are blended within therange of about 50:50 by weight to about 95:5 by weight (i.e., firstmaterial:second material). In one such exemplary embodiment, the blendof first and second materials is about 50:50 by weight. The benefits ofsuch blends over the first material by itself are improved water orvapor barrier properties, and thus improved product shelf life; improvedheat sealability; a reduced coefficient of friction; improvedmoldability or mold flow rates; and a reduction in hystereses losses. Asmay be recognized by those skilled in the pertinent art based on theteachings herein, these numbers and materials are only exemplary,however, and may be changed if desired or otherwise required in aparticular system.

Threaded Syringe-Type Dispenser to Control Movement of Plunger

In FIGS. 11-17, another syringe-type dispenser embodying the presentinvention is indicated generally by the reference numeral 210. Manycomponents of the syringe 210 are the same as those in the syringes 10and 110 described above, and therefore like reference numerals precededby the numeral “2”, or preceded by the numeral “2” instead of thenumeral “1”, are used to indicate like elements. The primary differenceof the syringe 210 in comparison to the syringes 10 and 110 is that thesyringe 210 includes a threaded plunger and partially threaded uppersyringe portion as the means for controlling the movement of the plungerin the syringe.

As shown in FIGS. 11-14, the syringe 210 includes a syringe body 212, aplunger 214 which fits within the syringe body, and a dispensing tip 216with a one-way valve. As shown in FIGS. 11 and 12, the body 212 of thesyringe has an upper portion 218 and a lower portion 220. The outside ofthe upper portion 218 is square shaped to permit the syringe to beeasily gripped and allow lateral movement of the body walls uponrotating the plunger, as described further below. The invention is notlimited in this regard, however, and the outside of the upper portion ofthe body may be any desired shape. The lower portion 220 of the syringeis generally cylindrical. As shown in FIGS. 13 and 14, the upper portion218 is connected to the lower portion 220 by a tapered portion 222. Atthe outer end of the upper portion 218, means may be provided to gripthe syringe, such as a flange 219 or other gripping means.

Referring to FIGS. 11 and 15, the inner wall of the upper portion 218 ofthe syringe 210 includes a plurality of partial threads 221. As shown inFIG. 15, each of the partial threads 221 is generally defined by an arcof the circle representing the thread diameter of a fully threaded innercylinder. The partial threads 221 are equally spaced relative to eachother, and each of the partial threads 221 has the same inner and outerthread diameter. In the preferred embodiment shown in FIGS. 11 and 15,each of the partial threads occupies approximately ⅛ of thecircumference of a fully threaded inner cylinder. The invention is notlimited in this regard, however, and each of the partial threads canoccupy any desired portion of the full circumference of a fully threadedinner cylinder in accordance with the teachings herein. Also, any numberof partial threads can be used, provided there are at least two opposingpartial thread portions for threadedly engaging the plunger, asdescribed further below.

As shown in FIGS. 11 and 15, a plurality of unthreaded sections 223 arelocated in the upper portion 218 of the syringe between the partialthreads 221. The unthreaded sections 223 have a larger diameter (orlateral or radial extent) than the outside diameter of the partialthreads 221, and preferably have a larger diameter (or lateral or radialextent) than the largest diameter thread on the plunger 214, asdescribed further below. In the embodiment shown in FIGS. 11 and 15, theupper portion 218 of the syringe 210 has a square shape with the partialthreads 221 centered on each of the four inner faces of the upperportion 218 of the syringe, and the unthreaded sections 223 aregenerally located in the corners of the square-shaped body section. Asmay be recognized by those of ordinary skill in the pertinent art basedon the teachings herein, the inner surface of the upper portion 218 ofthe syringe 210 may have any desired shape provided that the partialthreads on the inner surface define arcs of a circle of the desireddiameter.

Referring to FIGS. 12-14, the inner wall 238 of the lower portion 220 ofthe syringe body 212 defines a smooth cylindrical cavity and has anapproximately constant inner diameter over the axial length of the lowerportion 220. The lower portion 220 of the syringe is used to contain thesubstance to be dispensed, and is dimensioned to frictionally engage thetip of the plunger described further below. The inner diameter of thelower portion 220 is preferably constant to ensure that a specificquantity of the medicament or other substance contained therein isdispensed from the syringe for a pre-determined distance of travel bythe plunger 214.

At the end of the lower portion of the syringe body, a dispensing tipindicated generally by the reference number 216 is provided to allow thesubstance contained in the lower portion 220 of the syringe to flow fromthe syringe as the plunger 214 is inserted into the lower portion. In acurrently preferred embodiment, the dispensing tip 216 includes a flange928 that defines an annular U-shaped channel 230. The dispensing tip 216includes an elongated center shaft or post 232. A plurality ofcylindrical openings 256 each communicates with the chamber in the lowerportion 220 of the syringe to provide a path to dispense the substancecontained in the syringe.

The syringe preferably includes a one-way valve mechanism at thedispensing tip of the syringe to prevent air or other contaminants fromentering the substance contained in the syringe through the dispensingtip. Referring to FIGS. 12 and 13, the one-way valve is formed by fixinga flexible cover 254 on the dispensing tip 216 of the syringe body. Theflexible cover is preferably made of an elastomeric material. Theinterior surface of the flexible cover is shaped to fit over the flange228 on the dispensing tip 216 and to fit integrally within the annularU-channel 230 which extends around the dispensing tip. The flexiblecover 254 forms an interference fit with the center shaft 232 on thedispensing tip. The flexible cover 254 extends from the outer surface ofthe lower portion 220 of the syringe body 212 to approximately the endof the center shaft 232 of the dispensing tip 216.

At the base of the center shaft 232, and as shown best in FIGS. 13 and14, the plurality of cylindrical openings 256 extend through thedispensing tip. The cylindrical openings 256 communicate with the cavityin the lower portion 220 of the syringe and provide a path through whichthe substance in the cavity in the lower portion 220 flows as theplunger 214 is advanced into the lower portion 220 of the syringe. Theinterference fit between the flexible cover 254 and the center shaft 232forms a normally-closed valve to hermetically seal the cylindricalopenings 256 until a dose of the substance contained in the syringe isdelivered. The portion of the flexible cover 254 that interfaces withthe center shaft 232 may be tapered such that the thickness is greaternear the base of the center shaft and gradually reduces to a lesserthickness near the end of the center shaft.

In an alternative embodiment of the invention, the one-way valve may beomitted. The center shaft 232 may be provided with a central cylindricalchannel that communicates with the cavity in the lower portion 220 ofthe syringe to provide a path for dispensing the substance contained inthe syringe. In other embodiments of the invention, other appropriatedispensing tip mechanisms known to those skilled in the art can befixedly attached to the syringe body. For example, the conventionalconnection device marketed under the trade name LUER-LOK can be used atthe dispensing tip of the syringe to allow attachment of disposableneedles. Other needle connection means, such as threaded fittings,elastomeric plugs, or fitted end caps equally may be used to attach aneedle to the end of the syringe. The lower end of the syringe body maybe shaped or threaded as required to accommodate the selected needleconnection means. A cap or other means (not shown) to hermetically sealthe dispensing end of the syringe may be used until the needle isconnected to the syringe to dispense the medicament or other substancetherein.

Referring now to FIGS. 11 and 16, the plunger 214 comprises a tip 240, alower drive portion 242 and an upper guide portion 244. The face surface246 of the tip 240 contacts the medicament or other substance in thecavity in the lower portion 220 of the syringe during use. The tip 240is shaped and dimensioned to fit frictionally into the cavity in thelower portion 220 of the syringe body such that the medicament or othersubstance dose not escape between the tip 240 and the inner surface ofthe lower portion 220 of the syringe as the tip 240 is inserted into thelower portion 220. The tip 240 may be made of any suitable material thatis currently or later becomes known to those skilled in the art thatwill not react with the medicament or other substance contained in thesyringe. If desired, a fusible stopper, such as the fusible stopperdescribed in detail above, can be fixedly attached to the plunger tohermetically seal the cavity in the lower portion.

The drive portion 242 of the plunger 214 is shaped and dimensioned tofit slidingly within the lower portion 220 of the syringe body. Theoutside diameter of the drive portion 242 is preferably at leastslightly less than the inside diameter of the lower portion 220 of thesyringe body to reduce the frictional force generated by movement of theplunger within the syringe body. The drive portion 242 should besufficiently long to be fully inserted into the cavity in the lowerportion 220 of the syringe body when the plunger is in its fullyinserted position.

Referring to FIGS. 11, 12 and 16, the upper guide portion 244 of theplunger has a threaded section 245 with a thread pitch complementary tothe pitch of the partial threads 221 on the inner wall of the upperportion 218 of the syringe. As shown in FIG. 17, in a preferredembodiment wherein the syringe body and plunger are made of a moldableplastic, the thread pitch, P, is approximately 0.8 mm and the threadangle is approximately 90°. When the syringe body and the plunger aremade of molded plastic, a thread angle of approximately 90° permitseasier removal of the molded parts from the molds.

As shown in FIG. 15, the threads 245 on the upper guide structure have avariable thread diameter. The threads on the upper guide structure aredivided generally into eight sections. In four of the eight sections,indicated generally by the reference number 247, the threads have athread diameter and pitch approximately equal and complementary to thethread diameter and pitch of the partial threads 221 on the inner wallof the upper portion 218 of the syringe. These four sections each occupyapproximately ⅛ of the circumference of the upper guide portion of theplunger, and are spaced equally apart relative to each other.

In the remaining four sections of threads on the plunger, indicatedgenerally by the reference number 249, each of the sections of threadshave two regions defined by the thread diameter in each region. In thefirst region, indicated generally by the reference number 251, theplunger threads have a gradually increasing thread diameter, beginningwith a thread diameter equal to the thread diameter of the partialthreads in the upper portion 218 of the syringe, and ending at a pointwhere the thread diameter on the plunger first reaches its maximumdiameter. In the second region 253, the plunger threads have a constantdiameter that is larger than the diameter of partial threads 221 in theupper portion 218 of the syringe. Each of the four sections of varyingdiameter threads occupies approximately ⅛ of the circumference of theupper guide portion of the plunger. A knob or other gripping portion 252is formed at the upper end of the plunger 214 to provide means for theuser to grip the plunger during use.

The threads 247, 249 on the upper guide portion of the plunger cooperatewith the partial threads 221 formed on the inner wall of the upperportion 218 of the syringe body to provide means for controlling thetravel of the plunger into the syringe in a stepwise manner. As shown inFIG. 13, after the syringe has been filled with the substance to bedispensed, the plunger is positioned such that the tip 240 of theplunger is in contact with the medicament or other substance containedin the chamber in the lower portion 220 of the syringe body with thethreads 247 fully engaged in the partial threads 221 in the upperportion 218 of the syringe. The plunger 214 is positioned such that thepartial threads 221 in the syringe body are engaged only by the foursections of threads 247 on the upper guide portion 244 that have athread diameter equal to the thread diameter of the partial threads 221in the upper guide portion. As shown in FIG. 15, in this position, thelargest diameter threads 249 on the upper guide portion 244 of theplunger are located in the unthreaded sections 223 of the upper portion218 of the syringe body between the partial threads 221.

To deliver a metered dose of the substance from the syringe, and asindicated by the arrow in FIG. 15, the plunger 214 is rotated in theclockwise direction causing the plunger to travel into the syringe body.As the plunger 214 is rotated, the partial threads 221 in the upperportion 218 of the syringe are each progressively engaged by the largerdiameter threads 251, 253 on the upper guide portion 244 of the plunger214. Because the threads on the plunger 214 progressively increase indiameter as the plunger is rotated in the clockwise direction, the upperportion 218 of the syringe body 212 is forced to expand, andprogressively greater force must be applied to the plunger to cause itto rotate.

In the embodiment shown in FIGS. 11-17, when the plunger 214 completesrotation through ¼ of a full revolution, the largest diameter threads253 on the upper guide portion 244 of the plunger disengage from thepartial threads 221 in the upper portion 218 of the syringe body, andthe smaller diameter threads 247 on the upper guide portion 244 of theplunger are completely engaged in the partial threads 221 in the syringebody. The upper portion 218 of the syringe body rapidly returns to itsoriginal dimension, and the plunger is locked in position untilsufficient force is applied to the plunger to cause the larger diameterthreads on the plunger to engage and move through the partial threads onthe syringe body. In addition, the plunger cannot be rotated in theopposite direction (i.e., counter-clockwise) because the trailing edgeof each large diameter threaded portion 253 will engage the adjacentedge of each threaded portion 221 of the body and thereby prevent suchmovement.

By controlling the pitch of the partial threads in the syringe body andthe pitch of the complementary threads on the plunger, the amount ofmedicament or other substance delivered for each ¼ turn of the plungercan be precisely controlled. For example, in a preferred embodiment, thelower chamber 220 of the syringe has an approximately 6.18 mm insidediameter, and the threaded portions have a thread pitch of approximately0.8 mm. Rotation of the plunger by ¼ turn causes the plunger to displacea volume of approximately 6 microliters from the lower portion of thesyringe. Accordingly, approximately 6 microliters of the substancecontained in the syringe is delivered through the dispensing tip whenthe plunger is rotated ¼ turn. Greater doses of the substance can bedelivered by increasing the number of ¼ rotations of the plunger, i.e. ½rotation will deliver 12 microliters, ¾ rotations will deliver 18microliters, one full rotation will deliver 24 microliters, etc.

Syringe-Type Dispenser with Elastomeric Outer Body

In FIGS. 18-21, another syringe-type dispenser is indicated generally bythe reference numeral 310. Many of the components of the syringe 310 arethe same as those in the syringes 10, 110 and 210 described above, andtherefore like reference numerals preceded by the numeral “3”, orpreceded by the numeral “3” instead of the numerals “1” or “2”, are usedto indicate like elements. The primary differences in the syringe 310 incomparison to the syringes 10, 110 and 210 is that the syringe 310includes a threaded plunger and threaded elements in the upper syringeportion as the means for controlling the movement of the plunger, andthe syringe 310 includes an outer elastomeric cover.

As shown in FIGS. 18-19, the syringe 310 comprises a syringe body 312, aplunger 314 which fits within the syringe body, and a dispensing tip316. The syringe body 312 includes an inner portion 311 and anelastomeric outer cover 315 which encases the outer surface of the innerportion 311. The inner portion 311 is preferably made from moldedplastic. The inner portion 311 of the syringe body 312 includes an upperportion 318 and a lower portion 320, wherein the upper portion has alarger diameter than the lower portion. The upper portion 318 isconnected to the lower portion 320 by a tapered portion 322. Thedispenser is not limited in this regard, however, and the upper portionand the lower portion may be any desired shape or diameter. Where thediameters of the upper portion and the lower portion are the same, thetapered portion may be eliminated.

As shown in FIGS. 20 and 21, the inner walls of the upper portion 318and the lower portion 320 define cylindrical cavities. The upper portion318 of the syringe comprises a plurality of axially-elongated threadedelements 317 extending from the tapered portion 322 of the syringe body312 to the top of the syringe. Each of the threaded elements 317 isgenerally defined by an arc of the circle representing the threaddiameter of a fully threaded inner cylinder. The sides of the threadedelements 317 define a plurality of axially-elongated slots 319 in theupper portion 318 which likewise extend from the tapered portion 322 tothe top of the syringe. The depth of the slots 319 may extend completelythrough the syringe body 312, or may extend only partially through thesyringe body.

Referring again to FIGS. 18 and 19, the inner wall 338 of the lowerportion 320 of the syringe body 312 defines a smooth cylindrical cavityand has an approximately constant inner diameter over the axial lengthof the lower portion 320. The lower portion 320 of the syringe is usedto contain the substance to be dispensed, and is dimensioned tofrictionally engage the base of the plunger, as described further below.The inner diameter of the lower portion 320 is preferably constant toensure that a specific quantity of the medicament or other substancecontained therein is dispensed from the syringe for a pre-determineddistance of travel by the plunger 314.

At the end of the lower portion of the syringe body, a dispensing tipindicated generally by the reference number 316 is provided to allow thesubstance contained in the lower portion 320 of the syringe to flow fromthe syringe as the plunger 314 is inserted into the lower portion. In apreferred embodiment shown in FIG. 18, the dispensing tip 316 includes aflange 328 that defines an annular U-shaped channel (not shown) similarto the U-shaped channel 30 of the syringe 10 described above. Thedispensing tip 316 includes an elongated center shaft or post 332.

The syringe preferably includes a one-way valve mechanism at thedispensing tip of the syringe to prevent air or other contaminants fromentering the substance contained in the syringe through the dispensingtip. The one-way valve is formed by fixing a flexible cover (not shown)on the dispensing tip 316 of the syringe body. The flexible cover ispreferably made of an elastomeric material. The interior surface of theflexible cover is shaped to fit over the flange 328 on the dispensingtip 316 and to fit integrally within the annular U-channel which extendsaround the dispensing tip. The flexible cover forms an interference fitwith the center shaft 332 on the dispensing tip. The flexible coverextends from the outer surface of the lower portion 320 of the syringe312 to approximately the end of the center shaft 332 of the dispensingtip 316.

At the base of the center shaft 332, a plurality of cylindrical openings356 extend through the dispensing tip. The cylindrical openings 356communicate with the chamber in the lower portion 320 of the syringe andprovide a path through which the substance in the cavity in the lowerportion 320 flows as the plunger 314 is advanced into the lower portion320 of the syringe. The interference fit between the flexible cover andthe center shaft 332 forms a normally-closed valve to hermetically sealthe cylindrical openings 356 until a dose of the substance contained inthe syringe is delivered. The portion of the flexible cover thatinterfaces with the center shaft 332 may be tapered such that thethickness is greater near the base of the center shaft and graduallyreduces to a lesser thickness near the end of the center shaft.

In an alternative embodiment, the one-way valve may be omitted. Thecenter shaft 332 may be provided with a central cylindrical channel thatcommunicates with the cavity in the lower portion 320 of the syringe toprovide a path for dispensing the substance contained in the syringe. Inother embodiments, other appropriate dispensing tip mechanisms that arecurrently or later become known to those skilled in the art can befixedly attached to the syringe body. For example, the conventionalconnection device marketed under the trade name LUER-LOK can be used atthe dispensing tip of the syringe to allow attachment of disposableneedles. Other needle connection means, such as threaded fittings,elastomeric plugs, or fitted end caps equally may be used to attach aneedle to the end of the syringe. The lower end of the syringe body maybe shaped or threaded as required to accommodate the selected needleconnection means. A cap or other means (not shown) to hermetically sealthe dispensing end of the syringe may be used until the needle isconnected to the syringe to dispense the medicament or other substancetherein.

The elastomeric outer cover 315 is comprised of a flexible material thatis capable of being expanded by the application of force to the innerwall of the cover and returning substantially to its original shape whenthe applied force is removed. The elastomeric outer cover is preferablyformed by over molding an elastomeric material around the inner syringebody. The elastomeric outer cover may be any desired thickness and mayinclude features that allow ease of use, such as, for example, thegripping indentations 307 in the outer cover shown in FIG. 18.

Referring to FIGS. 18-20, the plunger 320 comprises a base 340, a lowerdrive portion 342, and an upper guide portion 344. The face surface 346of the base 340 contacts the medicament or other substance in the cavityin the lower portion 320 of the syringe during use. The base 340 isshaped and dimensioned to fit frictionally into the cavity in the lowerportion 340 of the syringe body such that the medicament or othersubstance dose not escape between the base and the inner surface of thelower portion 320 of the syringe as the base 340 is inserted into thelower portion 320. The base 340 may be made of any suitable materialknown to those skilled in the art that will not react with themedicament or other substance contained in the syringe. If desired, asshown in FIG. 18, a fusible stopper, such as the fusible stopperdescribed in detail above, can be fixedly attached to the plunger tohermetically seal the cavity in the lower portion.

The drive portion 342 of the plunger 314 is shaped and dimensioned tofit slidingly within the lower portion 320 of the syringe body. Theoutside diameter of the drive portion 342 is preferably at leastslightly less than the inside diameter of the lower portion 320 of thesyringe body to reduce the frictional force generated by movement of theplunger within the syringe body. The drive portion 342 should besufficiently long to be fully inserted into the cavity in the lowerportion 320 of the syringe body when the plunger is in its fullyinserted position.

As shown in FIG. 19, the upper guide portion 344 of the plunger 314 hasa plurality of threaded sections 345 with a thread pitch complementaryto the pitch of the threaded elements 317 on the inner wall of the upperportion 318 of the syringe. In a preferred embodiment wherein thesyringe body and plunger are made of a moldable plastic, the threadpitch is approximately 0.8 mm and the thread angle is approximately 90°.When the syringe body and the plunger are made of molded plastic, athread angle of approximately 90° permits easier removal of the moldedparts from the molds.

As shown in FIG. 20, each of the threaded sections 345 on the upperguide portion 344 of the plunger 314 have a variable thread diameter.Each of the threaded sections on the plunger has a first region whereinthe thread diameter is approximately equal and complementary to thethread diameter of the threaded elements 317, a second region whereinthe plunger threads have a gradually increasing thread diameter, and athe third region wherein the plunger threads have a constant diameterthat is larger than the diameter of the threaded elements 317 in theupper portion 318 of the syringe. The second region and third region ofthe threads on the plunger together will generally extend over an areathat is equal to the area occupied by the slots 319 between the threadedelements 317 in the upper portion 318 of the syringe to allow the secondand third threaded regions to be received within the slots. As shown inFIG. 20, this can be accomplished by using a plurality of tine-likethreaded members 321 on the upper guide portion 344 of the plunger 314.The tine-like threaded members 321 are sized to fit into the slotsbetween the threaded elements 317 in the upper portion 318 of thesyringe. A knob or other gripping portion 352 is formed at the upper endof the plunger 314 to provide means for the user to grip the plungerduring use.

To deliver a metered dose of the substance from the syringe, the plunger314 is rotated in the direction, normally clockwise, causing the plungerto travel into the syringe body. As the plunger 314 is rotated, thethreaded elements 317 in the upper portion 318 of the syringe are eachprogressively engaged by the larger diameter threads on the second andthird threaded regions on the upper guide portion 344 of the plunger314. Because the threads on the plunger progressively increase indiameter as the plunger is rotated in the clockwise direction, the upperportion 318 of the syringe and the elastomeric outer cover 311 expand,and progressively greater force must be applied to the plunger to causeit to rotate. As the larger diameter threads on the upper guidestructure 344 rotate through the threaded elements 317 of the upperportion 318 and into the slots 319 between the threaded elements, theupper portion of the syringe and elastomeric outer cover rapidly returnto their original diameter.

As described above, the dose of substance delivered can be preciselycontrolled by establishing the thread pitch and the distance betweenthreaded portions such that the plunger assembly travels the desireddistance into the lower chamber for each turn of the plunger. A largerdose may be delivered by increasing the number of turns of the plungerfor each dose delivered.

Syringe-Type Dispensers with Means for Preventing Residual Seepage ofSubstance through the Dispensing Tip

In FIGS. 22 through 30 another embodiment of the syringe-type dispenseris indicated generally by the reference numeral 410. The syringe 410 isthe same or similar in many respects to each of the syringe-typedispensers described above with reference to FIGS. 1-21, and thereforelike reference numbers preceded by the numeral “4”, or preceded by thenumeral “4” instead of the numerals “1” through “3”, are used toindicate like elements.

The syringe 410 differs from the syringes described above in that thesyringe 410 includes a different one-way valve on the dispensing tip 416and includes means for preventing residual seepage of the substancecontained in the sealed chamber 420 through the dispensing tip. As shownin FIGS. 22 and 23, the dispensing tip 416 of the syringe body 412defines two flow openings 456 that are located on diametrically oppositesides of the dispensing tip relative to each other, and are orientedapproximately perpendicular to the axis of the tip. The valve cover 454forms an interference fit with the valve seat defined by the centralpost 432 of the dispensing tip in the same manner as the valvesdescribed above. In addition, as with the one-way valves describedabove, the valve cover 454 defines a gradually decreasing wall thicknessin the axial direction from the interior to the exterior end of thecover to facilitate opening and closing of the valve upon movement ofthe plunger. All other factors being equal, the one-way valve of FIGS.22 and 23 typically requires a higher valve opening pressure than thevalves described above in connection with FIGS. 1-21. In the valvesdescribed above and shown, for example, in FIGS. 13 and 14, the flowopenings 256 extend in approximately the axial direction of thedispensing tip and therefore the substance flows axially out of thedispensing tip. The laterally-extending flow openings 456 of FIGS. 22and 23, on the other hand, require the substance to flow through anapproximately 90° turn, thus requiring higher valve opening pressures(all other factors being equal) in order to move the substance throughthe valve.

The syringe 410 further includes means for effecting step-wise movementof the plunger within the syringe body and dispensing a predeterminedamount of substance from the chamber of the syringe body. In theillustrated embodiment, the means for effecting step-wise movementincludes a plurality of discrete thread portions 421 formed on aninterior wall of the upper portion 418 of the syringe body, and aplurality of corresponding thread portions formed on the upper guideportion 444 of the plunger. As described in further detail below, and ina manner similar to the other embodiments of the dispenser describedabove, the discrete thread portions on the syringe body and plungercooperate to provide a “click-action” type actuating mechanism thatallows for incremental or step-wise movement of the plunger within thesyringe body, and that preferably further provides a “click” (that maybe discernable to the user by sound and/or feel) upon movement of theplunger through each incremental or step-wise movement. In addition, thediscrete thread portions further provide means for preventing residualseepage of the substance contained within the chamber 420 through theone-way valve of the dispensing tip 416 upon terminating each discreteincremental or step-wise movement of the plunger.

As shown typically in FIG. 24, the upper guide portion 418 of thesyringe body 412 defines four discrete thread portions 421 equallyspaced approximately 90° relative to each other about the axis of thesyringe body. As can be seen, each thread portion 421 extends alongapproximately the full axial extent of the upper guide portion 418. Thethread portions 421 are substantially the same as the thread portions221 described above in connection with FIG. 11, and therefore eachthread portion 421 defines the same thread diameter and pitch as theother thread portions 421. In addition, the corners 423 of the upperguide portion 418 define laterally extending voids between adjacentthread portions 421.

As shown typically in FIG. 25, the upper guide portion 444 of theplunger 414 defines a plurality of pairs of first discrete threadsegments 484, 484 located on diametrically opposite sides of the upperguide portion relative to each other; a plurality of pairs of seconddiscrete thread segments 486, 486 located on diametrically oppositesides of the upper guide portion relative to each other and angularlyspaced relative to the first discrete thread segments 484, 484; and aplurality of third discrete thread segments 488, 488, wherein each pairof diametrically opposed third thread segments 488, 488 are locatedbetween a respective pair of first diametrically opposed first threadsegments 484, 484, and a respective pair of second diametrically opposedsecond thread segments 486, 486. As shown typically in FIG. 25, each360° section of thread of the upper guide portion 444 of the plungerdefines, when moving clockwise away from the arrow in FIG. 25, a firstthread segment 484, a third thread segment 488, a second thread segment486, a third thread segment 488, a first thread segment 484, a thirdthread segment 488, a second thread segment 486, and a third threadsegment 488.

As shown typically in FIG. 25, each discrete thread section 421 of theupper guide portion 418 of the syringe body defines an outer diameter“D1”, and each second thread section 486 defines approximately the samethread diameter “D1”. Each third thread section 488 defines a secondthread diameter D2 that is less than the first thread diameter D1 of thesyringe body threads 421. Each first thread segment 484 defines avarying thread diameter that gradually increases from a third threaddiameter D3 at the leading edge 490 of the respective first threadsegment 484, to a fourth thread diameter D4 at the trailing edge 492 ofthe respective first thread segment 484. The third thread diameter D3 atthe leading edge of each first thread segment 484 is slightly greaterthan the first thread diameter D1 of the syringe body threads 421, andthe fourth thread diameter D4 is greater than both the first and thirdthread diameters D1 and D3, respectively. In the illustrated embodiment,the first thread diameter D1 is approximately 10 mm, the second threaddiameter D2 is approximately 9.8 mm, the third thread diameter D3 isapproximately 10.3 mm, and the fourth diameter D4 is approximately 10.6mm. As may be recognized by those of ordinary skill in the pertinent artbased on the teachings herein, these dimensions are only exemplary, andmay be changed as desired depending upon the other dimensions of thedispenser or otherwise as required or might be desired for anyparticular application of the dispenser.

As also shown typically in FIG. 25, the leading edge 490 of each firstthread segment 484 defines an approximately 45° chamfer extendingbetween the respective first and third thread segments 484 and 488,respectively, to facilitate slidable engagement of the first threadsegments 484 of the plunger with the corresponding thread segments 421of the syringe body. Similarly, the leading edge 494 of each secondthread segment 486 of the plunger defines an approximately 45° chamferextending between the respective second and third thread segments 486and 488, respectively, to facilitate slidable engagement of the secondthread segments 484 of the plunger with the corresponding threadsegments 421 of the syringe body. As may be recognized by those ofordinary skill in the pertinent art based on the teachings herein, thedegree and/or shape of the leading edge of the thread segments describedherein are only exemplary, and may be changed as desired depending uponthe requirements of a particular dispenser or otherwise to facilitatethe operation of the dispenser.

With reference to FIGS. 25 through 27, in order to dispense thehermetically sealed substance from the chamber 420 through thedispensing tip 416, the plunger is rotating in a clockwise manner. Asshown in the progressive views of FIGS. 25 through 27, rotation of theplunger ¼ turn (or about 90°) in the clockwise direction causes thefirst thread segments 484 to slidingly engage the respective syringebody threads 421 and, in turn, laterally expand the respective sidewalls of the syringe body outward, as indicated in the exemplary brokenlines in FIG. 26. More specifically, as the leading edge 490 of eachfirst thread segment threadedly engages the corresponding thread segment421 of the syringe body, the respective portion of the side wall of thesyringe body is flexed outwardly to locally match the leading edgediameter D3 of the first thread segments 484 of the plunger. As theplunger is further rotated in the clockwise direction, the side wall ofthe syringe body is flexed further outwardly by the gradually increasingdiameters of the first thread segments 484 (i.e., as the first threadsegment surface engaging the syringe body increases in diameter from D3to D4). Then, as shown typically in FIG. 27, upon rotating a full ¼ turnin the clockwise direction, the trailing edge 492 of each first threadsegment 484 of the plunger passes through the respective thread segment421 of the syringe body, and only the small diameter (D2) threadsegments 488 of the plunger are located in contact with the syringe bodythread segments 421. Upon passage of the first thread segments 484 ofthe plunger through the syringe body thread segments 421, the opposinglateral walls of the syringe body snap back or laterally inwardly, thuscreating a click-action sensation for the user and thereby signaling tothe user that the plunger has completed ¼ turn and dispensed thepredetermined dosage of substance through the dispensing tip. As showntypically in FIG. 27, the difference in diameter between the trailingedge of each first thread segment 484 and the leading edge of theadjacent third thread segment 488 creates a stop surface 496 preventingreverse (or counterclockwise) movement of the plunger. As can be seen,counterclockwise movement of the plunger causes the stop surfaces 496 ofthe plunger to engage the adjacent side walls of the thread segments 421of the syringe body to thereby prevent further reverse (orcounterclockwise) movement of the plunger.

With reference to FIGS. 27 and 28, when located in the rest position(i.e., with the third thread segments 488 of the plunger engaging thesyringe body threads 421, and the first and second thread segments 484and 486, respectively, of the plunger located within the voids 423 ofthe syringe body), the plunger is allowed limited axial movement inorder to relieve any residual pressure within the hermetically sealedchamber 420 of the syringe body (FIG. 23), and thereby substantiallyprevent any such pressure from causing any residual seepage of thesubstance through the dispensing tip. As shown typically in FIG. 28,because the diameter (D2) of the third thread segments 488 of theplunger is less than the diameter (D1) of the syringe body threads 421,the plunger is permitted to move axially a distance “X”. Accordingly, ifafter dispensing the pre-metered dose of substance through thedispensing tip there is residual pressure within the hermetically sealedchamber 420, or if any such pressure develops due, for example, todifferential thermal expansion or otherwise because of changingenvironmental conditions, the plunger is permitted to move axiallyinwardly (i.e., away from the dispensing tip) by the distance “X” inorder to relieve such pressure. As a result, any such residual pressureis substantially prevented from forcing any of the substance through thedispensing tip and thus creating a messy or otherwise undesirableresidue on the surface of the dispensing tip.

In the illustrated embodiment, the distance “X” is approximately 0.2 mm.In addition, the threads on the plunger and on the syringe body areapproximately 90° threads. However, as may be recognized by those ofordinary skill in the pertinent art based on the teachings herein, thesedimensions and thread angles are only exemplary, and may be changed asdesired depending upon the application and/or other requirements of thesyringe or other dispenser of the present invention.

As shown typically in FIGS. 22 and 23, the syringe 410 preferablyincludes a cover 496 for protecting the dispensing tip 416 when not inuse. In the illustrated embodiment, the cover extends axially over thelower portion of the syringe body. As shown typically in FIGS. 22 and23, the lower portion of the syringe body 412 may include an annular rib498 or other structural feature to facilitate releasably securing thecover to the syringe body.

Syringe-Type Dispensers with Concealed, Movable Plungers

In FIGS. 31 and 32, another syringe-type dispenser is indicatedgenerally by the reference numeral 510. The syringe-type dispenser 510is the same as or similar in many respects to each of the syringe-typedispensers described above with reference to FIGS. 1-30, and thereforelike reference numbers preceded by the numeral “5”, or preceded by thenumeral “5” instead of the numerals “1” through “4”, are used toindicate like elements.

The syringe-type dispenser 510 differs from the syringe-type dispensersdescribed above in connection with FIGS. 1-30 in that the plunger 514 isfully concealed within the syringe body 512, and the syringe furtherincludes a mechanism 511 for driving the plunger within the syringebody. The base or inner end of the plunger 514 defines an axial bore 513including a first or inner set of threads 515 formed therein, and anannular flange 517 defining two diametrically opposed, axially-extendingslots 519 formed thereon. The syringe body 512 defines a pair ofdiametrically opposed, axially-extending ribs 521 formed on an innerwall thereof and slidably received within the slots 519 formed on theperipheral flange 517 of the plunger. A drive wheel 523 is rotatablymounted in the open end of the syringe body 512, and includes anaxially-extending drive shaft 525 defining a second set of threads 527formed on the outer surface thereof. As shown in FIGS. 31 and 32, thesecond set of threads 527 on the drive shaft 525 threadedly engage thefirst set of threads 515 formed at the base of the plunger to axiallymove the plunger upon rotating the drive wheel 523. The drive wheel 523further includes an annular, exposed gripping surface 529 formed at thebase of the syringe body for gripping and rotation by the user. Uponrotating the gripping surface 529, the drive shaft 527 rotatably drivesthe plunger 514 and, in turn, moves the plunger tip 560 through thesealed chamber 520 to dispense the substance from the chamber throughthe dispensing tip.

As may be recognized by those skilled in the pertinent art based on theteachings herein, the syringe body 512 may take the same shape as thesyringe body 412 described above, and threads may be formed on thesyringe body and plunger in the same manner as described above to createa click-action type actuating mechanism for effecting step-wise orincremental movement of the plunger, and/or to prevent any pressurewithin the hermetically sealed chamber from causing residual seepage ofany substance through the dispensing tip.

In FIGS. 33 and 34, another syringe-type dispenser is indicatedgenerally by the reference numeral 610. The syringe-type dispenser 610is the same as or similar in many respects to each of the syringe-typedispensers described above with reference to FIGS. 1-32, and thereforelike reference numbers preceded by the numeral “6”, or preceded by thenumeral “6” instead of the numerals “1” through “5”, are used toindicate like elements.

The syringe-type dispenser 610 differs from the syringe-type dispensersdescribed above in connection with FIGS. 1-30 in that the plunger 614 isfully concealed within the syringe body 612, and the syringe furtherincludes a mechanism 611 for driving the plunger within the syringebody. The base or inner end of the plunger 614 defines an annular flange617 including a first set of threads 627 formed thereon, and a pair ofdiametrically opposed slots 619 formed through the base adjacent to theplunger shaft. The syringe body 612 defines a second set of threads 615axially extending along the inner wall of the syringe body forthreadedly engaging the corresponding threads 627 of the plunger. Adrive wheel 623 is rotatably mounted in the open end of the syringe body612, and includes a pair of diametrically opposed, axially-extendingdrive posts 621. As shown in FIGS. 33 and 34, the second set of threads627 on the plunger threadedly engage the first set of threads 615 formedon the syringe body to axially move the plunger upon rotating the drivewheel 623. In addition, the posts 621 are slidably received through theslots 619 of the plunger to cause rotation and, in turn, axial movementof the plunger upon rotating the drive wheel. The drive wheel 623further includes an annular, exposed gripping surface 629 formed at thebase of the syringe body for gripping and rotation by the user. Uponrotating the gripping surface 629, the axially-extending posts 621rotatably drive the plunger 614 and, in turn, move the plunger tip 660through the sealed chamber 620 to dispense the substance from thechamber through the dispensing tip.

Turning to FIGS. 38-40, In FIGS. 33 and 34, another syringe-typedispenser is indicated generally by the reference numeral 610′. Thedispenser 610′ is the same in many respects as the dispenser 610described above in connection with FIGS. 33 and 34, and therefore likereference numerals including the prime symbol (“′”) are used to indicatelike elements. The primary difference of the dispenser 610′ incomparison to the dispenser 610 is that the dispenser 610 includes asyringe body 612′ that defines the same shape as the syringe body 412described above, and the threads 615′ on the syringe body and thethreads 627′ on the plunger 614′ are formed in the same manner asdescribed above to create a click-action type actuating mechanism foreffecting step-wise or incremental movement of the plunger and toprevent any pressure within the hermetically sealed chamber from causingresidual seepage of any substance through the dispensing tip.

Syringe-Type Dispensers with Uniquely-Shaped Dispensing Tips forCosmetic Applications

In FIGS. 35 and 36, another syringe-type dispenser embodying the presentinvention is indicated generally by the reference numeral 710. Thesyringe-type dispenser 710 is the same as or similar in many respects toeach of the syringe-type dispensers described above with reference toFIGS. 1-34, and therefore like reference numbers preceded by the numeral“7”, or preceded by the numeral “7” instead of the numerals “1” through“6”, are used to indicate like elements.

As can be seen, the dispensing tip 716 of the syringe-type dispenser 710defines an approximately concave dispensing surface 717 shaped toconformably contact a user's lips or other surface contour. In theillustrated embodiment, the dispensing tip 716 defines a single opening756 for the flow of the substance contained within the sealed chamber720 therethrough. However, as may be recognized by those skilled in thepertinent art based on the teachings herein, the dispensing tip mayinclude any desired number of such openings in any desired configurationdepending upon the requirements or needs of a particular application.The valve cover 754 may be made of any of the types of flexible,polymeric materials described above in connection with the previousembodiments. For example, the valve cover 754 may be molded of therelatively elastic polymeric material sold under the trademark KRATON20A, and the valve seat 732 may be molded of the relatively harderpolymeric material sold under the trademark KRATON 65A. These materialsare only exemplary, however, and may be any of numerous differentmaterials that are currently or later become known for performing thefunctions of the valve cover and valve seat as described herein.

Although not shown, the syringe-type dispenser 710 preferably includes aplunger and syringe body as described above in connection with any ofthe previous embodiments, and preferably further includes a click-actiontype actuating mechanism for effecting step-wise or incremental movementof the plunger, and/or to prevent any pressure within the hermeticallysealed chamber from causing residual seepage of any substance throughthe dispensing tip.

In FIG. 37, another syringe-type dispenser embodying the presentinvention is indicated generally by the reference numeral 810. Thesyringe-type dispenser 810 is the same as or similar in many respects toeach of the syringe-type dispensers described above with reference toFIGS. 1-36, and therefore like reference numbers preceded by the numeralor preceded by the numeral “8” instead of the numerals “1” through “7”,are used to indicate like elements.

The primary difference of the syringe-type dispenser 810 in comparisonto the syringe type dispenser 710 described above, is that thesyringe-type dispenser 810 includes a substantially frusto-conicalshaped dispensing surface 817 that tapers inwardly toward a roundeddispensing tip. This type of uniquely-shaped tip is particularly suitedfor the application of cosmetics, such as lip gloss, eye color,concealer or cover-up, shine control, mattifying make-up, eye shadow,eye glaze, line minimizing make-up, or other make-ups or cosmetics.

One advantage of the syringe-type dispensers of FIGS. 35-37 is that theyare particularly well suited for cosmetic applications, such as thedispensing of lipsticks, lip gloss, eye color cremes or liquids, andcover-ups and concealers to cover, for example, wrinkles, blemishes etc.The contoured dispensing tips provide a dispensing surface thatconformably contacts the skin, such as the user's lips, eyelids or otherfacial surfaces, and comfortably applies a metered dose of the cosmeticsubstance to the spot or area of interest. In addition, the conformingsurface formed by the elastic valve covers comfortably contacts theuser's skin and, if desired, may be made of a material substantiallymatching or emulating the softness of a user's finger to therebycomfortably apply the cosmetic substance to the skin.

Yet another advantage of the syringe-type dispensers of the presentinvention is that they will retain the cosmetic or other substance in asealed, airless condition within the sealed chamber of the syringe body,thereby allowing the dispenser to contain and dispense multiple dosesover any desired period of time while continuously maintaining thesubstance in a sealed, sterile condition throughout such virtuallyunlimited period of use.

Yet another advantage of the syringe-type dispensers of the presentdisclosure is that they dispense precisely metered dosages of substancestherefrom, and furthermore, may include the anti-seepage featuredescribed above, to thereby prevent the collection of a messy orotherwise unwanted substance residue on the dispensing tip, even aftermultiple applications or usages of the same dispenser.

As may be recognized by those of ordinary skill in the pertinent artbased on the teachings herein, numerous changes and modifications may bemade to the above-described and other embodiments of the presentinvention without departing from its spirit or scope as defined in theappended claims. For example, the dispensers of the present inventionmay be made of any of numerous different materials that are currentlyknown or later become available for dispensers of this type. Similarly,the dispensers of the present invention can take any of numerousdifferent shapes and/or configurations that might be desired orotherwise required for particular applications. The means forcontrolling relative movement of the plunger and housing likewise maytake any of numerous different configurations that are currently known,or are later developed for achieving incremental and/or step-wisemovement to, in turn, dispense metered doses of substances. Similarly,the structure for preventing residual seepage of substance from thedispenser, such as by relieving internal pressure within thesubstance-containing chamber, may take the form of any of numerousdifferent structures that are currently known, or are later developedfor performing this function. Likewise, the structure for creating a“click-action” in order to signal to the user the discharge of a metereddose of substance may take any of numerous different structures orconfigurations that are currently known, or are later developed forperforming this function. In addition, the one-way valves and/ordispensing tips of the dispensers of the present invention may take anyof numerous different shapes and/or configurations. For example, asdescribed above, the dispensing tips may define any of numerousdifferent shapes to facilitate, for example, application of thesubstance to a person's skin. Accordingly, this detailed description ofpreferred embodiments is to be taken in an illustrative rather than alimiting sense.

1-20. (canceled)
 21. A method for aseptically storing and dispensing a sterile food product, comprising the following steps: (i) maintaining a sterile food product hermetically sealed within a variable-volume storage chamber of a dispenser including a one-way valve coupled in fluid communication with the variable-volume storage chamber, wherein the one-way valve includes an elastic valve member forming a normally closed valve opening; (ii) dispensing a plurality of different portions of the sterile food product at different points in time from the variable-volume storage chamber through the one-way valve by pressurizing sterile food at an inlet to the normally closed valve opening and in turn moving the elastic valve member between a normally closed position and an open position with at least a segment of the valve member spaced away from the closed position to connect the valve opening in fluid communication with the variable-volume storage chamber and thereby allow the passage of sterile food product from the variable-volume storage chamber through the valve opening; and (iii) maintaining the sterile food product within the variable-volume storage chamber sterile and hermetically sealed with respect to ambient atmosphere throughout steps (i) and (ii).
 22. A method as defined in claim 21, further comprising the following steps: sterile filling the variable-volume storage chamber with the food product; and hermetically sealing the sterile food product within the variable-volume storage chamber.
 23. A method as defined in claim 21, further comprising the step of substantially preventing the ingress of air or other contaminants through the one-way valve and into the variable-volume storage chamber during steps (iv) and (v).
 24. A method as defined in claim 21, wherein the dispensing step includes dispensing a plurality of different portions of the food product at different points in time from the variable-volume storage chamber through the one-way valve.
 25. A method as defined in claim 22, further comprising the step of sterilizing the food product prior to the step of sterile filling the variable-volume storage chamber with the food product.
 26. A method as defined in claim 21, further comprising the step of manually manipulating a device that exerts pressure on the food product contained within a chamber of the dispenser and, in turn, dispensing a portion of the food product from the variable-volume storage chamber through the one-way valve.
 27. A method as defined in claim 21, wherein the dispenser include a penetrable and thermally resealable portion in fluid communication with the variable-volume storage chamber, and the method further comprises the steps of: sterilizing an exposed surface of the penetrable and resealable portion; penetrating the penetrable and thermally resealable portion with a filling member coupled in fluid communication with a source of the sterile food product; introducing the sterile food product through the filling member and into the variable-volume storage chamber; withdrawing the filling member from the penetrable and thermally resealable portion; and applying sufficient thermal energy to the penetrated region of the penetrable and thermally resealable portion to fuse the penetrated region and form a substantially gas-tight seal between the penetrated region and the variable-volume storage chamber.
 28. A dispenser for storing and dispensing a sterile food product, comprising: a variable-volume storage chamber, and a one-way valve coupled in fluid communication with the variable-volume storage chamber and including an elastic valve member forming a normally closed, axially-extending valve opening, wherein the valve member is movable between a normally closed position, and an open position with at least a segment of the elastic valve member spaced away from the closed position to connect the valve opening in fluid communication with the variable-volume storage chamber and thereby allow the passage of the sterile food product through the valve opening, the variable-volume storage chamber is sterile filled with the food product, the sterile food product is hermetically sealed in the variable-volume storage chamber, and the dispenser maintains the food product within the variable-volume storage chamber sterile and hermetically sealed with respect to ambient atmosphere throughout dispensing a plurality of different portions of the food product from the storage chamber through the one-way valve.
 29. A dispenser as defined in claim 28, further comprising a housing defining the variable-volume storage chamber.
 30. A dispenser as defined in claim 28, further comprising a device that exerts pressure on the food product contained within a chamber of the dispenser in order to dispense a plurality of different portions of the food product from the variable-volume storage chamber through the one-way valve.
 31. A dispenser as defined in claim 30, further comprising a mechanism coupled to the device to move the device, exert pressure on the food product, and dispense a portion of the food product through the one-way valve.
 32. A dispenser for storing sterile food and dispensing multiple portions of the sterile food therefrom, comprising: a hermetically sealed, variable-volume storage chamber containing therein multiple portions of the sterile food hermetically sealed with respect to ambient atmosphere; a one-way valve comprising a valve member formed of an elastic material and forming a normally closed valve opening and an inlet to the valve opening in fluid communication with the variable-volume storage chamber, wherein the valve member is movable radially in response to food at the inlet to the valve opening exceeding a valve opening pressure between (i) a normally closed position and (ii) an open position with at least a segment of the valve member spaced radially away from the closed position to connect the valve opening in fluid communication with the variable-volume storage chamber and thereby allow sterile food to be dispensed through the valve opening; and a device in fluid communication with the variable-volume storage chamber and one-way valve and configured to exert pressure on food at the inlet of the valve opening to exceed the valve opening pressure and dispense a portion of the sterile food through the one-way valve, wherein during dispensing of sterile food through the one-way valve, the one-way valve and storage chamber maintain food remaining in the storage chamber sterile and sealed with respect to ambient atmosphere.
 33. A dispenser as defined in claim 32, further comprising a manually-engageable mechanism coupled to the device to move the device, exert pressure on the food, and dispense a portion of the food through the one-way valve.
 34. A dispenser for storing and dispensing multiple portions of a sterile food, comprising: a variable-volume storage chamber including a plurality of portions of sterile food hermetically sealed therein; means coupled in fluid communication with the variable-volume storage chamber for forming a normally closed opening, for moving between a normally closed position, and an open position with at least a segment said means spaced away from the closed position to connect the opening in fluid communication with the variable-volume storage chamber and thereby allow the passage of sterile food through the opening, and for maintaining the food within the variable-volume storage chamber sterile and hermetically sealed with respect to ambient atmosphere throughout dispensing a plurality of different portions of the sterile food from the storage chamber therethrough; and a device in fluid communication with the variable-volume storage chamber and said means and configured to exert pressure on sterile food at the opening and dispense a portion of the sterile food through said means.
 35. A dispenser as defined in claim 34, wherein said means is a one-way valve comprising a valve member formed of an elastic material and forming a normally closed valve opening and an inlet to the valve opening in fluid communication with the variable-volume storage chamber, wherein the valve member is movable radially in response to food at the inlet to the valve opening exceeding a valve opening pressure between (i) a normally closed position and (ii) an open position with at least a segment of the valve member spaced radially away from the closed position to connect the valve opening in fluid communication with the variable-volume storage chamber and thereby allow sterile food to be dispensed through the valve opening. 